I have a Potterton Suprima 40 boiler. It recently noticed that when on timer for the hot water it continually fires up and shuts off on a one or two minute cycle. The cylinder thermostat is set at 60 degrees and I have hot water.

However, if I simply select the option for a '1 hour' boost then the cycling does not occur as frequent.

Am I correct in thinking that the pump may play a part in this or is a motherboard issue (this was replaced 1 year ago and I'm fairly sure it wasn't an occurrence prior to this)?